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BMC veterinary research2025; 21(1); 90; doi: 10.1186/s12917-025-04569-3

Oxytocin in horse saliva: validation of a highly sensitive assay and a pilot report about changes in equine gastric ulcer syndrome.

Abstract: Equine gastric ulcer syndrome (EGUS) is a frequent disease in horses that comprises two different entities: equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD). This disease considerably reduces the quality of life of affected horses and can negatively affect performance. Saliva contains biomarkers, such as oxytocin, that have been used as a welfare indicator and can develop a function as a protective factor against stress-induced changes in gastric function due to its gastric antisecretory and antiulcer effects. The objective of this work was to evaluate changes in salivary oxytocin concentrations in healthy and EGUS horses. For this purpose, an immunoassay based on AlphaLISA technology was validated for the quantification of salivary oxytocin and applied in a total of 102 horses divided into 5 groups: 25 with both EGUS, 23 with only EGGD, 21 with only ESGD, 19 horses with other diseases, and 14 healthy horses. Results: The analytical validation of the method showed good precision and linearity under dilution. Salivary oxytocin concentrations in healthy horses were higher compared to horses with both ESGD and EGGD and only EGGD. Salivary oxytocin concentrations in horses with only ESGD were higher compared to horses with both ESGD and EGGD and horses with only EGGD. In addition, salivary oxytocin concentrations in horses with other diseases different from ESGD were significantly increased compared to horses with both ESGD and EGGD and horses with only EGGD. Conclusions: This report validates a new assay that can measure oxytocin in saliva in horses in a precise and accurate way. The lower oxytocin values in horses with EGGD and both EGGD and ESGD than in horses with ESGD, horses with other diseases, and healthy horses could indicate a possible relation of oxytocin with this disease.
Publication Date: 2025-02-22 PubMed ID: 39987089PubMed Central: PMC11847335DOI: 10.1186/s12917-025-04569-3Google Scholar: Lookup
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  • Journal Article
  • Validation Study

Summary

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The research paper investigates changes in the levels of oxytocin, a hormone detectable in horse saliva, in healthy and sick horses suffering from equine gastric ulcer syndrome (EGUS) . The researchers validated a new assay, based on AlphaLISA technology, to measure salivary oxytocin and applied it to five different horse groups. The results validated the method and showed an apparent correlation between oxytocin levels and EGUS disease status.

Objective and Approach

  • The purpose of the research was to study the fluctuations in salivary oxytocin concentrations among healthy horses and those suffering from EGUS, a common equine disease that encompasses equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD).
  • This study utilized AlphaLISA technology to develop an immunoassay, which is a biochemical test that measures the concentration of a substance in solution, in this case, oxytocin in horse saliva.
  • The researchers examined a total of 102 horses, assigning them to five different groups according to their health and disease status.

Validation of the Method

  • The assay, based on AlphaLISA technology, was shown to be effective in quantifying salivary oxytocin.
  • The methodology demonstrated satisfactory precision and linearity under dilution, confirming the reliability of the test.

Results of the Study

  • The concentration of salivary oxytocin was found to be higher in healthy horses as compared to horses diagnosed with both ESGD and EGGD or only EGGD.
  • Horses that were only diagnosed with ESGD showed higher levels of salivary oxytocin than horses with both ESGD and EGGD or only EGGD.
  • Interestingly, horses with non-EGUS diseases demonstrated increased salivary oxytocin concentrations compared to both ESGD and EGGD and EGGD-only affected horses.

Conclusions

  • The study successfully validated a new assay that accurately measures oxytocin in horse saliva.
  • The lower levels of oxytocin observed in horses with EGGD and both EGGD and ESGD, in comparison to horses only with ESGD, those with other diseases, or healthy horses could suggest a potential relationship between oxytocin levels and the presence of this disease.

Cite This Article

APA
Botía M, Muñoz-Prieto A, Martínez-Subiela S, Martín-Cuervo M, Hansen S, Manteca X, Cerón JJ, López-Arjona M. (2025). Oxytocin in horse saliva: validation of a highly sensitive assay and a pilot report about changes in equine gastric ulcer syndrome. BMC Vet Res, 21(1), 90. https://doi.org/10.1186/s12917-025-04569-3

Publication

ISSN: 1746-6148
NlmUniqueID: 101249759
Country: England
Language: English
Volume: 21
Issue: 1
Pages: 90

Researcher Affiliations

Botía, María
  • Interdisciplinary Laboratory of Clinical Analysis (INTERLAB-UMU), Department of Animal Medicine and Surgery, Veterinary School, Regional Campus of International Excellence Mare Nostrum, University of Murcia, 30100, Murcia, Spain.
Muñoz-Prieto, Alberto
  • Interdisciplinary Laboratory of Clinical Analysis (INTERLAB-UMU), Department of Animal Medicine and Surgery, Veterinary School, Regional Campus of International Excellence Mare Nostrum, University of Murcia, 30100, Murcia, Spain. alberto.munoz@um.es.
Martínez-Subiela, Silvia
  • Interdisciplinary Laboratory of Clinical Analysis (INTERLAB-UMU), Department of Animal Medicine and Surgery, Veterinary School, Regional Campus of International Excellence Mare Nostrum, University of Murcia, 30100, Murcia, Spain.
Martín-Cuervo, María
  • Department of Animal Medicine, Faculty of Veterinary Medicine of Cáceres, University of Extremadura, Av. de La Universidad S-N, Cáceres, 10005, Spain.
Hansen, Sanni
  • Department of Veterinary Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Manteca, Xavier
  • Department of Animal and Food Science, Autonomous University of Barcelona, Cerdanyola del Vallès, Barcelona, 08193, Spain.
Cerón, José Joaquín
  • Interdisciplinary Laboratory of Clinical Analysis (INTERLAB-UMU), Department of Animal Medicine and Surgery, Veterinary School, Regional Campus of International Excellence Mare Nostrum, University of Murcia, 30100, Murcia, Spain.
López-Arjona, Marina
  • Department of Animal and Food Science, Autonomous University of Barcelona, Cerdanyola del Vallès, Barcelona, 08193, Spain.

MeSH Terms

  • Animals
  • Horses
  • Horse Diseases / metabolism
  • Horse Diseases / diagnosis
  • Oxytocin / analysis
  • Oxytocin / metabolism
  • Stomach Ulcer / veterinary
  • Stomach Ulcer / metabolism
  • Saliva / chemistry
  • Pilot Projects
  • Male
  • Female
  • Immunoassay / veterinary
  • Immunoassay / methods
  • Biomarkers / analysis

Grant Funding

  • RYC2021-033660-I / Ministerio de Ciencia, Innovación y Universidades
  • FJC2021-047105-I / Ministerio de Ciencia, Innovación y Universidades

Conflict of Interest Statement

Declarations. Ethics approval and consent to participate: The animal study protocol was approved by the Murcia University Ethics Committee (protocol code CEEA 288/2017, approval date: 13 January 2016) and by the local committee of the Large Animal Teaching Hospital of the University of Copenhagen (protocol code #2020–020, approval date: 1 January 2020 and # 2024–001, approval date: 1 January 2024). Informed consent from owners was obtained to use the horses in the current study. Consent for publication: All authors have approved the manuscript and agree with its publication. Competing interests: The authors declare no competing interests.

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